{{Parts infobox |image = Keys.scad.png |designers = [[User:Tim|Timothy Schmidt]] |date = 2021 |vitamins = |materials = |transformations = |lifecycles = |tools = [[Saws]], [[CNC Mills]] |parts = |techniques = |files = |suppliers = |git = }} [[Category:Parts]] [[Category:Motion parts]] =Introduction= In mechanical engineering, a key is a machine element used to connect a rotating machine element to a [[keyed shafts|shaft]]. The key prevents relative rotation between the two parts and may enable torque transmission. For a key to function, the shaft and rotating machine element must have a keyway and a keyseat, which is a slot and pocket in which the key fits. The whole system is called a keyed joint. A keyed joint may allow relative axial movement between the parts. Commonly keyed components include gears, pulleys, [[shaft couplers]], and [[washers]]. =Challenges= =Approaches= =References= * [[https://en.wikipedia.org/wiki/Key_(engineering)|Key (engineering)]] * [[https://www.surpluscenter.com/Power-Transmission/Shafting/Key-Stock/1-4-Square-Key-1-5-Long-G-G-Mfg-411-0424-1-5030-25-A.axd|1/4" square key]]